Printing systems such as copiers, printers, facsimile devices or other systems having a print engine for creating visual images, graphics, texts, etc. on a page or other printable medium typically include various media feeding systems for introducing original image media or printable media into the system. Examples include thermal transfer printers. Typically, a thermal transfer printer is a printer which prints on media by melting a portion of coating of ribbon stream so that it stays attached to the media on which the print is applied. It contrasts with direct thermal printing where no ribbon is present in the process. Typically, thermal transfer printers comprise a supply spindle operable for supplying a media web and ribbon, a print station having a printhead, and a take up spindle. During a printing operation, new ribbon and media is fed from the supply spindle to the print station for printing and then the ribbon is wound up by the take up spindle while the media is exited from the print station.
As the ribbon exits the print station it is rewound on the take up spindle. When printing sensitive information such as, for example, social security numbers, account numbers, and other similar private information, the unused portion of the ribbon will contain a negative image of the subject sensitive information. Undesirably, conventional thermal transfer printing methods provide no means of security to the information which is printed. Because the used ribbon on the take up spindle possesses a negative image of the previously printed image, the secrecy of the information printed on the media may be jeopardized.
It is therefore be desirable to provide a printing system and method which provides security means to information printed on media during a thermal transfer printing operation. It is also be desirable to provide a printing method which allows for the used ribbon of such a thermal transfer printer to be obscured such that the negative image is unable to be read.